package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseThreadLocal;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符,
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();//

        log.info("拦截到请求：{}",requestURI);

        //定义不需要处理的请求路径,即放行静态资源
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/login",
                "/user/sendMsg"
        };

        //2、判断本次请求是否需要处理
        boolean check = check(urls, requestURI);

        //3、如果不需要处理，则直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1、判断登录状态，如果已登录，则直接放行
        Long id = (Long) request.getSession().getAttribute("employeeLogin");
        if(id != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("employeeLogin"));
            BaseThreadLocal.set(id);//过滤器把一个session对象得到的id放入ThreadLocal中
            filterChain.doFilter(request,response);
            BaseThreadLocal.remove();//防止ThreadLocal溢出
            return;
        }

        //4-2、判断登录状态，如果已登录，则直接放行

        if(request.getSession().getAttribute("user") != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("user"));
            //从session中获取用户id
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseThreadLocal.set(userId);//过滤器把一个session对象得到的id放入ThreadLocal中
            filterChain.doFilter(request,response);
            //BaseThreadLocal.remove();//防止ThreadLocal溢出
            return;
        }

        log.info("用户未登录");
        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }
    /*
    *路劲匹配,检查是否须要放行
    * */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }
}
